Machine for making window bags



Feb. 14, 1956 H. L. BARTELT MACHINE FOR MAKING WINDOW BAGS Filed April14, 1952 5 Sheets-Sheet 1 Feb. 14. 1956 H. L.. BARTELT MACHINE FORMAKING WINDOW BAGS 3 Sheets-Sheet 2 Filed April 14, 1952 Feb. 14, 1956Filed April 14, 19,52

H. l.. BARTELT MACHINE FOR MAKING WINDOW BAGS 3 Sheets-Sheet 3 Wou/'oldbl. )"5 QAM/pw' man* frommen/f UIltCd StatCS ce 2,734,431

tenfed Feb. 14, 195s- MAGHINE FOR- WINDGW ABAGS par lif'fa Donald E.Banen Airplicaiion April .14; 1952; serial No.V v22:2;119 i6 aiii. (iii."93:5

which between the member and the bracket. During a dwell of the strips,the rise of a cam 50 on the camshaft 25 engages a follower roller 51carried at the lower end of the lever 42 turning the latter about itspivot against the force of a contractile spring 518, which acts betweenthe frame 24 and the lower end of the lever, and swinging the shoeforward to cross-seal the strips.

Severance of the bags is accomplished herein by two vertical opposedblades 52 and 53 disposed on opposite sides of the strips 18 and 19 andlocated beyond the feed rollers 29 and 30 at the cutting station 21. Theblade 53 is stationary on the frame 24 and the other blade 52 is mountedon the upper end of an upright lever 54 pivoted intermediate its ends ona rock shaft 55. During dwelling of the strips, the rise of a cam 56 onthe camshaft 25 engages a follower 57 journaled on the lower end of thelever 54 rocking the latter and swinging the blade 52 toward the blade53 to cut the strips between the edges of the seal 13a.

As more fully set forth in my prior application, the machine thus fardescribed operates in successive cycles each comprising one revolutionof the camshaft 25 to complete the formation of one bag and cut the sameolf from the leading end of the strip. In the first part of the cycle,the rollers 29 and 30 are turned to draw material from the roll 35 pastthe folder 39 and advance the folded strip a distance equal to the widthof the bag as determined by the photocell controlled mechanism 33.During the ensuing dwell of the strip, the heated shoe 40 and the cutter52 are advanced simultaneously to form the cross seal 13a at the station20 and sever the previously formed seal at the station 21.

In accordance with the present invention, the strip feeding, sealactuating and cut-off mechanisms of the bag forming machine are utilizedadvantageously to perform the additional functions of forming the windowsheet 15, locating the same properly with respect to the window opening14, sealing the sheet to the wall 11 around the window, and cutting thesheet to a desired length. To accomplish this, a strip 59 of transparentwindow material is placed alongside the strip 17 before folding of thelatter so that the window strip becomes attached to the folded strip bythe cross seal 13a and is thus held properly positioned relative to thewindow 14 preparatory to sealing of the window strip to the outer strip18 at a subsequent sealing station 60.

,ln order that the transparent strip 59 may enter the bag forming pathin the proper relation to the strips 18 and 19, a roll 61 (Figs. l and2) of transparent strip material is carried on the ends of the arms 37above the roll 35 where it is unwound and advanced over thestraightening rollers 36 alongside the sheet 17 of bag material. Theroll 61 is supported by a horizontal shaft 62 the ends of which arejournaled in brackets 63 rigid with and depending from the outer ends ofthe arms 37. Preferably the transparent strip 59 is somewhat less thanhalf as wide as the sheet 17 and is unwound with its left edge, asviewed in Fig. 2, lying along the center of the sheet. The properrelation of the strip and the sheet is obtained by placing the roll 61on the right side of the shaft 62 and holding it in that position bycollars 64 which abut against the ends of the roll and are secured tothe shaft by set screws 65.

From the rolls 35 and 61, the sheet 17 and the transparent strip 59 areadvanced over the folding mechanism 39 where the sheet is foldedlongitudinally. Since the transparent strip lies over only one side ofthe sheet (Fig. 6), it is not folded and, upon leaving the foldingmechanism, is disposed between and parallel to the strips 18 and 19formed by the fold as shown in Figs. 7 and 8.

To form the window 14, a cutter or punch 66 is disposed at a station 58between the folding mechanism 39 and the cross sealing station 20 whereit may be operated by the camshaft 25 during each dwell of the strips 18and 19 to cut the window in the strip 18. Herein, the

punch comprises a male die 67 (Fig. 3) on the inside of the strip 18 anda female die 68 on the outside, the two dies having complemental cuttingsurfaces which, when moved together, punch out the hole 14. In thepresent instance, the hole is generally square and hence the cuttingsurfaces of the dies are also square as will be seen in Fig. 1.

The male die 67 is mounted on the front of a iiat vertical plate 69projecting downwardly between the strip 1S and the transparent strip 59from a horizontal arm 70 fast on an upright bracket 71 which is suitablybolted to the frame 24. Since the window cutting station 58 is inadvance of the cross sealing station 20, the strip 18 is free to pass infront of the plate 69 while the strips 19 and 59 pass behind and,therefore, the plate does not interfere with the advance of the strips.The female die 68 is supported by a rigid vertical plate 72 carried onthe upper end of an upright lever 73 pivoted intermediate its ends on ashaft 74 secured to the frame. Acting between the frame and the lowerportion of the lever is a contractile spring 75 which normally urges thefemale die away from the male die and holds a follower roller 76journaled on the lower end of the lever against a cam 77 on the camshaft25. While the strips are dwelling and the cross sealing and cut-offoperations are being performed, a rise 78 of the cam engages thefollower roller to swing the lever and move the female die toward themale die thus punching out a portion 79 of the strip 18 to form thewindow. During the cutting, the plate 69 is held against lateralshifting or bending by a vertical idler roller 80 journaled on thebracket 71 near the bottom of the plate and bearing against the latterthrough the strips 19 and S9 to serve as a backing.

The cut out portion 79 is ejected through a hole 81 formed in the plate72 and alined with the dies 67 and 68. lf desired, the ejection may beassisted by air jets tiowing from horizontal passages 82 (Fig. 3) formedin the male die and communicating with a compressed air supply line 83through a vertical passage 84 in the plate 69. A valve S5 (Fig. 1) isinterposed in the supply line and is actuated by a cam 86 on thecamshaft 25 in timed relation with the swinging of the lever 73 so thatcompressed air is admitted to the passages 82 immediately after theportion 79 is punched out by the dies.

In order that the strip 18 may ride over the male die 67 during the nextadvance without being torn around the window 14 by the die, stripper 678(Fig. 9) are disposed along the opposite side edges of the die and serveto guide the strip outwardly around the cutting edges of the die. Asshown, the strippers 67a are in the form of strips riveted to the plate69 along their outer edges with their inner edges 67b bent outwardly tolie alongside and ush with the side edges of the die. When the lever 73swings the female die 68 forwardly, the latter depresses the stripperedges 67ID permitting the dies to punch the window and, as the femaledie is retracted, the stripper edges spring out even with the male dieto present a smooth continuous surface over which the strip 18 movesduring the next advance by the feed rollers 29 and 30.

From the punching station 58, the strips 18, 19, and 59 are advanced tothe station 60 between the photocell 34 and the cross-sealing station 20Where the Iseal 16 joining the transparent strip 59 to the strip 18around the window 14 is formed. To form this seal, the areas of thestrip 18 surrounding the window and the corresponding areas of thetransparent strip are pressed together between two sealing elements 87and 88 (Figs. 4 and 5) disposed at the station 60. In the presentinstance, the scaling element 87 is a fiat hard rubber plate vertically,suspended from a horizontal arm 89 projecting forwardly from thebracket 47 upstanding from the frame 24 and projects into the bagforming path between the transparent strip 59 and the strip 19. Theother element 88 comprises a vertical plate 90 with laterally projectingshoes 91 having sealing srfaces facing the rubber plate S7. The sealingsurfaces are arranged to form a square alined with and corresponding insize and shape to the areas of the strips 18 and 59 joined by the seal16. Electrical heaters 92 are embedded in the plate 90 to heat the shoes91 above the fusing temperature of the bag material so that, when thesealing element 88 is moved to press' the strips 18 and 59 against thesurface of the rubber plate,` the strips are fused together.

The sealing element 88 is mounted on the upper end of a vertical leverwhich is rocked by a cam onthe camshaft 25 to swing the shoes 91 towardthe rubber plate 87. Preferably this sealing element is carried by thesame lever 42 which supports the shoe 40 and, for this purpose, issecured to the upper end of a second arm 93 rigid with and upstandingfrom the sleeve 43o-alongside and in ad- Vance of the lever arm 41. `Tomake the lever assembly more rigid, the shoes 40 and 91and the plate 90may be formed as a singlepiece 94 which is mounted on the arms 41 and 93by .bolts 95 projecting loosely through the arms and threaded into theback of the plate 90. Springs 96 surrounding the bolts and actingbetween the arms and the plate pertnit yielding of the latter so thatthe shoes 40 and 91 will engage the strip 18 firmly when pressing thestrips being sealed against the sealing element 87.

To maintain the rubber plate 87 vin its vertical position when the seal16 is being formed, a backing plate 97 is disposed in back of the rubberplate o'n the outside of the stripv19 and acts through the latter tohold the' rub ber plate against any substantial lateral shifting. Thebaekingplate is supported by the same bracket 47 which supports thebacking member 46 and is yieldably mounted onthebracket by bolts 98andsprings 99 in the same manner as the backing member ,46is mounted.

With` the transparent strip v59 attached to the strip 18, the feedrollers 29, and 30 unwind a length of the transparentstrip correspondingtothe length of bag material 17` unwound `from the roll 35 and advancethe transparentl strip concurrently with the wall strips 18 and 19. Thuseach portion of the strip 59 which is to formone of the transparentpieces 15 is maintained in aline'rnent withits associated window 14 bythe.A same mechanism which advances the strips 18 and 19. With thisconstrucf tion, the transparent piece is moved along the path of thelmachine inexact synchronism with the bag walls 11 and 12 without the useof additional feed mechanism.

When the bags reach the cutting vstation v21, the

transparent strip 59 is cut into lengths corresponding, .to the Width ofthe transparent pieces 15. By making the transparent pieces of the samevwidth as thebags, the blades 52 and 53 may be usedtocut the strip sincethe latterpasses between the blades with the strips 18 and 19'. Thus,when the blade 5 2 is swung forward, the transparent .piece is cnt frornthe strip 5 9 at the same time that thevend bag is severedfrom thestrips 18 an'd19. In the operation of the machine, the sheet materiall?is nn'wound from the roll 35 and drawn over the folding mechanism 89 toform the two strips 18 and y1 9. ,.Since the, transparent strip 59isrjoined tothe strip 1 8 by the seals 13a and 16, it is unv'voun'd fromthe roll 461 at .the s ame time and in synchronismwith the sheetmaterial 1 7. With the transparent strip lying over only one sideof thesheetmateriah it is not folded as it passes throughfth'e foldingmechanism fand is disposed between and 'parallel to the strip 18 and 19upon completion ofthe folding operation. During each revolution of thecamshaft 25, ythe three strips are advanced together by the feed rollersthrough a distance vcorresponding to the width ofthe bags 1 0 and then,d ue to the operationofthe indexing mechanism 38 and the brake 32a,.arestopped.

While the strips Aare dwelling, the rise o f each o f the cams 77, 50,and 56 engages its respective follower roller swinging the levers 73, 42, and 5 4. 'I husthefemale die 68 is swung toward the male die 67 andcuts a. window 14 in the vstrip 18 and; asthe female :die is retractedbythe 'sprin`g`75,",tl`1"e cam 86 actuates the valve 85 to permitcompressed air to flow through the jetV orifices 82 'and eject the cutotportion 79. While one window is being cut out, the shoes 91 seal thestrip 18 to the transparent strip 59 around another window which hadpreviously been cnt and advanced to the station 60 and tle shoe v'40,being o n .the same lever 42 as the shoes 91, swings' for- Ward with thelatter and cross-seals the three strips between the window ,beingsealedy and the window which was sealed during the previous cycle'. Atthe Sametime, the blades 52 and 53 cut the window sheet 15 from thetransparent "strip rand sever the bag 10 at the leading end of thestrips. After these o'pe'rations" have been coinpleted; the yindexingmechanismv `33 again is effective to turn' the feed rollers 29 and 30and advance the three strips vthrough a' distance e'qualo th'e width ofthe' bags and, during a subsequent dwell of the strips; the aboveoperations are repeated.

. ItY will be seen that a standard bag making Vmachine has been adaptedto cut the windows 14 in the bags 10; 'cut the window sheets .15 to theproper size, position the sheet accurately with respect to vthe Windowand seal the sheet `to 'the wall 1'1 around the window by the additionof only three vsimple mechanisms, namely, the shaft 62 and its supportfor mounting the roll 61 of transparent strip mat'eial 59,1lthepunchingv mechanism 66 and the sealing elements 87 and. 88. B`yusingthe feed rollers 29 and 30 and the knife blades 52 and 53 whichadvance and cut the strips 18 and 19 to -feed and cut the transparentstrip V59, the transparent window sheet 15 is positionedautomatically.with respect t'o the bag walls V11 and 12. This synchronized movement ofthe strips achieves `a lhigh degree of accuracy and; as a result; 'thetransparent sheet is always 'centered Vrelative to the 'vvindow V14V so'that ,the bags 10 are Vneatand well formed. In' addition,` such accuracyvisobtained without the use of special synchronizing mechanisms by.utiliiing vthe mechanisms already present in the standard maehine.

I claim as my invention:

1. A bag making machine comprising, means for supporting a rst strip ofmaterial and guiding the same endwis'e along a predetermined path,mechanism for supporting a transparent strip alongside said iirst strip,means disposed along said path andoperable to fold said rst striplongitudinally around said transparent strip, rollers disposed in saidpath beyond said vfolding meansv and en# gageable with opposite sides ofsaid folding stiip; an actuating mechanism for turning 'said 'rollersperiodi; cally to advance said folded strip in succes's'ii'l'eV stepsthrough distances corresponding to the width of the bags to be formed, Vsealing 'elements disposed along-said path and engageable duringdwelling of said strips the opposite sides of said folded strip to Vsealthe saine 'to said transparent strip transversely of 'the strips,iriearsin` Cluding a cutter disposed along said path and operable duringa dwell of the 'strips to cut a window in onfy de of said folded strip,ad "sealing members beyond id cutter anden'gageable with said one sideand said trnsparent strip tose'althe same together aroundfthe window.

2. Apparatus for making bags from two' outside4 n strips and anintermediate transparent strip, 4saidappiatratiis having, incombination, mechanism 'for supporting the three strips of material sideby side and Vadvent'ing the same endwise along a predetermined paththrough distances corresponding to the width of the bags to be formed,means including a cutter disposed along f path and operable tocut awindow in one of the outside strips during dwelling of the strips,sealing elements disposed along said pathbeyond said cutter and engage'-able with said transparent Astrip and said one outside strip to seal thetwo strips Vtogether about the windvv, sealing members disposed, beyondsad @ne an agresse with said outside strips to seal thesame to saidmiddle strip transversely of the strips and ybetween said windowsthereby to form a bag, and a second cutter disposed along said path andbeyond said sealing members and operable to cut said strips intermediatethe edges of the transverse seal.

3. Apparatus for making bags from two outside wall strips and anintermediate transparent strip, said apparatus having, in combination,mechanism for supporting the three strips of material side by side andadvancing the same endwise along a predetermined path through distancescorresponding to the Width of the bags to be formed, means including acutter disposed along said path and operable to cut a window in one ofthe outside strips during dwelling of the strips, sealing elementsdisposed along said path beyond said cutter and engageable with saidtransparent strip and said one outside strip to seal the two stripstogether about the window, and sealing members disposed beyond saidcutter and engageable with said outside strips to seal the same to saidmiddle strip transversely of the strips and between said windows therebyto form a bag.

4. In a bag making apparatus, the combination of, means for supporting arst strip of material and guiding the same endwise along a predeterminedpath, means disposed in said path and operable to fold said striplongitudinally, rollers disposed in said path beyond said folding meansand engageable with opposite sides of said -folded strip, an actuatingmechanism for turning said rollers periodically to advance said strip insuccessive steps through distances corresponding to the width of bags tobe formed, means including a cutter disposed along said path and movableinto engagement with said strip to cut a window in the same, means forguiding a strip of transparent material endwise along said path and oversaid windows, sealing elements disposed along said path and engageablewith the opposite sides of said rst strip to seal the same and saidtransparent strip together between said windows whereby said rollersadvance said transparent strip with said first strip, and sealingmembers beyond said cutter and engageable with both of said strips toseal the same together around said windows.

5. In a bag making machine having a plurality of stations successivelydisposed along a predetermined path, the combination of, a die memberdisposed at one of said stations and projecting into said path, asealing member projecting into said path at a subsequent station,mechanism for supporting and advancing two strips of outside wallmaterial and an intermediate transparent strip side by by side throughsuccessive steps along said path with a rst outside strip passing infront of said members, the second outside strip passing behind saidmembers and the middle strip passing behind said die member and in frontof said sealing member, a complemental die disposed in front of said diemember and movable into engagement with the same to cut a window in saidfirst outside strip, a sealing element disposed in front of said memberand movable into engagement with said first outside strip to press thesame and said middle strip against the member' and seal the stripstogether around said window, and means to move said die and said sealingelement during dwelling of said strips.

6. Bag making apparatus having, in combination, means for supporting twostrips of outside wall material and an intermediate transparent stripside by side and advancing the same endwise in successive steps along apredetermined path, means including a cutter disposed along said pathand operable during a dwell of the strips to cut a window in one of theouter strips, a member disposed along said path beyond said cutter andprojecting between the transparent strip and said one outer strip, saidmember having sealing surfaces facing said one outer strip andcorresponding in size and shape to the edges of the one outer striparound the window, a sealing element disposed adjacent said member andon the outside of the other of said outer' strips and having a sealingsurface facing the strips and extending transversely of the same, asealing unit disposed on the outside of said one outer strip and movabletoward and away from the strips, said unit having complemental sealingsurfaces opposing the surfaces on said member and a sealing surfaceopposing and complementing the surface on said element, and meansoperable during dwelling of the strips to move said sealing unit againstsaid strips to seal the three strips together transversely and to sealthe one outer strip and the transparent strip together around a window.

7. In a bag making machine having stations successively disposed along apredetermined path, the combination of, mechanism for supporting twostrips of outside wall material and an intermediate transparent stripside by side and advancing the same endwise along said path insuccessive steps, means including a cutter at one of said stations andoperable during a dwell of said strips to cut a window in one of theoutside strips, a sealing member disposed at a subsequent station andprojecting into said path and between the other outside strip and saidtransparent strip, a sealing element disposed at said last mentionedstation and movable toward the strips to press said one outside stripand said transparent strip against said sealing member and seal the twostrips together around said window, and means operable during a dwell ofthe strips to move said sealing element toward said sealing member.

8. In a machine for making window bags, the combination of, means forsupporting a first outside strip having windows formed therein atintervals of a predetermined distance, a second outside strip and anintermediate transparent strip in side by side relation, mechanism foradvancing said strips endwise and intermittently through saidpredetermined distance, a member disposed along the path of said stripsand projecting in between the other of said outside strips and saidtransparent strip, a second member disposed on the outside of saidwindow strip and opposing said first member, said members havingcomplemental sealing surfaces alined during dwelling of the strips withthe edges of said windows, and means operable during dwelling of thestrips to move said members together thereby to press said window stripand said transparent strip between said sealing surfaces and seal thetwo strips together around the window.

9. In a bag making machine having stations successively disposed along apredetermined path, the combination of, mechanism for supporting twostrips of outside wall material and an intermediate transparent stripside by side and advancing the same endwise in successive steps alongsaid path, a stationary member disposed at one of said stations andprojecting between the transparent strip and one of the outer strips, adie bodily supported on said member and having cutting surfaces facingsaid one outer strip, a movable die disposed at said one station andhaving cutting surfaces opposing and complementing the surfaces on thestationary die, means operable during dwelling of the strips to movesaid movable die toward said stationary die thereby to cut a window insaid one outer strip, and sealing elements disposed at a subsequentstation and engageable with the outer strips between the windows to sealthe outer strips to the transparent strip thereby to form bags.

l0. In a bag making machine having stations successively disposed alonga predetermined path, the combination of, means for supporting twostrips of material side by side, mechanism for advancing said stripsendwise along said path step by step through distances corresponding tothe width of the bags to be formed, a member disposed at one of saidstations and projecting between said strips, a die bodily supported onsaid member and having cutting surfaces facing one of said strips, amovable die disposed at said one station and having cutting surfacesopposing and complementing the surfaces of the die on said member, meansoperable during dwelling of the' strips to move said movable die towardsaid other die thereby to cut a portion out of said one strip, andsealing elements disposed at a station subsequent to said first stationand engageable with said strips to seal the same together transverselythereby to form 6 10 Grant et al Feb. 18, 1936 Flynn et al. May 17, 1938Moore May 20, 1941 Robinson Feb. 10, 1942 Stevens et al. June 13, 1950

